Currently, due to condition limitations such as radio frequency links of some types of user equipments (English full name: user equipment, UE for short), the UEs of these types cannot simultaneously transmit a physical uplink control channel (English full name: physical uplink control channel, PUCCH for short) and a physical uplink shared channel (English full name: physical uplink shared channel, PUSCH for short).
In the prior art, when such UE has both a PUCCH resource and a PUSCH resource, uplink control information (English full name: uplink control information, UCI for short) is carried on the PUSCH resource for transmission, and UCI does not need to be transmitted on the PUCCH resource. Based on a cell index (English full name: cell index), the UCI may be carried on a PUSCH resource of a cell with a minimum cell index, to avoid simultaneous transmission of PUCCH data and PUSCH data. For example, as shown in FIG. 1, in a subframe, a serving cell (English full name: serving cell) 1 and a serving cell 2 each have a PUSCH resource allocated by a base station. In this case, if UCI needs to be transmitted, the UCI is carried for transmission on a resource of the serving cell 1 based on a cell index.
It should be noted that a PUCCH resource may be in a licensed spectrum cell, for example, a primary serving cell (English full name: primary cell, Pcell for short) in a carrier aggregation cell. The carrier aggregation cell includes a licensed spectrum cell and an unlicensed spectrum cell, and the unlicensed spectrum cell uses an unlicensed spectrum. The unlicensed spectrum cell may be a licensed-assisted access (English full name: license-assisted access, LAA for short) cell, and the LAA cell can transmit a PUCCH resource and a PUSCH resource only when the LAA cell and the licensed spectrum cell perform carrier aggregation (English full name: carrier aggregation, CA for short).
A PUCCH may also be in a standalone licensed-assisted access LAA (standalone LAA) cell and can work independently without relying on the licensed spectrum cell. In other words, the unlicensed spectrum cell may also have a PUCCH resource.
However, in the unlicensed spectrum cell, before a base station (English full name: eNodeB, eNB for short) sends downlink data or UE sends uplink data, a channel access process such as a listen before talk (English full name: listen before talk, LBT for short) process needs to be completed. If the LBT succeeds, UCI is successfully sent; otherwise, UCI cannot be sent. As shown in FIG. 2, UCI is carried on a PUSCH resource of an LAA cell, but because LBT fails, the UCI cannot be transmitted to an eNB in time, consequently affecting uplink scheduling.